Portion of an article of footwear



FIG. 1 is a bottom perspective view of a portion of an article of footwear showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a front elevational view thereof; and,

FIG. 7 is a rear elevational view thereof.

The broken line showing of FIGS. 1-7 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a portion of an article of footwear, as shown and described. 